The study has found that (15)CEA detection has certain clinical application value in tumor diagnosis, differentiation of tumors to predict recurrence, etc. Studies have shown that CEA, a member of the immunoglobulin superfamily, belongs to the class of cell adhesion molecules, and its unique homophilic and xenophilic adhesion properties indicate that it plays a key role in the tumor metastasis mechanism (11). This evidence concerns the gene CEACAM5 and neoplasm.